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1.
Mol Ecol ; 33(2): e17213, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38014725

RESUMO

International policy recently adopted commitments to maintain genetic diversity in wild populations to secure their adaptive potential, including metrics to monitor temporal trends in genetic diversity - so-called indicators. A national programme for assessing trends in genetic diversity was recently initiated in Sweden. Relating to this effort, we systematically assess contemporary genome-wide temporal trends (40 years) in wild populations using the newly adopted indicators and whole genome sequencing (WGS). We use pooled and individual WGS data from brown trout (Salmo trutta) in eight alpine lakes in protected areas. Observed temporal trends in diversity metrics (nucleotide diversity, Watterson's Ï´ and heterozygosity) lie within proposed acceptable threshold values for six of the lakes, but with consistently low values in lakes above the tree line and declines observed in these northern-most lakes. Local effective population size is low in all lakes, highlighting the importance of continued protection of interconnected systems to allow genetic connectivity for long-term viability of these populations. Inbreeding (FROH ) spans 10%-30% and is mostly represented by ancient (<1 Mb) runs of homozygosity, with observations of little change in mutational load. We also investigate adaptive dynamics over evolutionarily short time frames (a few generations); identifying putative parallel selection across all lakes within a gene pertaining to skin pigmentation as well as candidates of selection unique to specific lakes and lake systems involved in reproduction and immunity. We demonstrate the utility of WGS for systematic monitoring of natural populations, a priority concern if genetic diversity is to be protected.


Assuntos
Variação Genética , Genoma , Animais , Variação Genética/genética , Genoma/genética , Truta/genética , Endogamia , Densidade Demográfica , Lagos
2.
J Cardiothorac Vasc Anesth ; 37(10): 2109-2113, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37120324

RESUMO

Endobronchial valves (EBVs) are a novel, minimally invasive bronchoscopic management technique for persistent air leaks that fail conservative therapy. Currently, 2 EBVs are available in the United States: the Spiration Valve System (Olympus, Redmond, WA) and the Zephyr Valve (Pulmonx, Redwood, CA). These valves are Food and Drug Administration-approved to reduce hyperinflation in emphysematous patients via bronchoscopic lung-volume reduction. However, more recently, the Spiration Valve has been granted a compassionate use exemption through the Food and Drug Administration for persistent postsurgical air leaks. Despite their popularity, these devices are not free from side effects. As an anesthesiologist, it is vital to be aware of the pathophysiology of this patient population so that safe and effective anesthetics may be provided during valve placement. Here, the use of EBVs is discussed in a patient who presented with a persistent air leak after a transthoracic needle aspiration that failed treatment due to persistent hypoxemia, warranting EBV removal.


Assuntos
Pneumotórax , Humanos , Pneumotórax/etiologia , Broncoscopia/métodos , Próteses e Implantes , Pneumonectomia/efeitos adversos , Hipóxia/etiologia , Hipóxia/cirurgia , Resultado do Tratamento
3.
Ecology ; 99(2): 474-487, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29231965

RESUMO

The central role of floristic diversity in maintaining habitat integrity and ecosystem function has propelled efforts to map and monitor its distribution across forest landscapes. While biodiversity studies have traditionally relied largely on ground-based observations, the immensity of the task of generating accurate, repeatable, and spatially-continuous data on biodiversity patterns at large scales has stimulated the development of remote-sensing methods for scaling up from field plot measurements. One such approach is through integrated LiDAR and hyperspectral remote-sensing. However, despite their efficiencies in cost and effort, LiDAR-hyperspectral sensors are still highly constrained in structurally- and taxonomically-heterogeneous forests - especially when species' cover is smaller than the image resolution, intertwined with neighboring taxa, or otherwise obscured by overlapping canopy strata. In light of these challenges, this study goes beyond the remote characterization of upper canopy diversity to instead model total vascular plant species richness in a continuous-cover North Carolina Piedmont forest landscape. We focus on two related, but parallel, tasks. First, we demonstrate an application of predictive biodiversity mapping, using nonparametric models trained with spatially-nested field plots and aerial LiDAR-hyperspectral data, to predict spatially-explicit landscape patterns in floristic diversity across seven spatial scales between 0.01-900 m2 . Second, we employ bivariate parametric models to test the significance of individual, remotely-sensed predictors of plant richness to determine how parameter estimates vary with scale. Cross-validated results indicate that predictive models were able to account for 15-70% of variance in plant richness, with LiDAR-derived estimates of topography and forest structural complexity, as well as spectral variance in hyperspectral imagery explaining the largest portion of variance in diversity levels. Importantly, bivariate tests provide evidence of scale-dependence among predictors, such that remotely-sensed variables significantly predict plant richness only at spatial scales that sufficiently subsume geolocational imprecision between remotely-sensed and field data, and best align with stand components including plant size and density, as well as canopy gaps and understory growth patterns. Beyond their insights into the scale-dependent patterns and drivers of plant diversity in Piedmont forests, these results highlight the potential of remotely-sensible essential biodiversity variables for mapping and monitoring landscape floristic diversity from air- and space-borne platforms.


Assuntos
Ecossistema , Tecnologia de Sensoriamento Remoto , Biodiversidade , Florestas , North Carolina
4.
Surg Endosc ; 30(10): 4653-8, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26895898

RESUMO

BACKGROUND: Ligation with either absorbable or non-absorbable sutures has been the traditional state of the art, but a proliferation of technology now offers a host of methods to close and divide vessels. Only limited data are available that objectively compare different vessel sealing methods. The objective of this study was to compare a broad variety of methods of surgical vessel closure in a reproducible, independent, standardized test-to-failure ex vivo pressure challenge. METHODS: Ten of the most common surgical sealing devices were represented in this study, including both mechanical and energy devices. Unfixed porcine carotid arteries were selected for testing. They were connected to a pump, and automated controlled infusion was initiated. Upon identification of a leak at the source of sealing, the maximum pressure in mmHg was logged. RESULTS: There were a total of 184 trials conducted using the 10 vessel sealing methods. The average burst pressure across all trials was 1100 mmHg with a range of 51.3-5171 mmHg. Suture-based methods displayed the highest average pressure until failure. Stapling methods showed the lowest burst pressures. All methods showed mean burst pressures above the "physiologically relevant" level of 250 mmHg. CONCLUSIONS: This study presents an independent, reproducible, ex vivo comparison of multiple methods of surgical arterial closure. In these laboratory conditions, tests to failure demonstrated widely varying sealing strength, highly dependent on method. All hemostatic modalities tested are capable of securing vessels safely and well above physiologic blood pressures, while suture-based methods were significantly stronger than other mechanical methods or modern energy devices.


Assuntos
Artérias Carótidas/cirurgia , Dispositivos de Oclusão Vascular , Animais , Laparoscopia , Ligadura , Modelos Anatômicos , Pressão , Técnicas de Sutura , Suturas , Suínos
5.
Cureus ; 16(6): e62371, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39006716

RESUMO

Introduction With the rising trends in breast cancer throughout the world, the traditional modus of intraoperative tissue dissection using a scalpel, scissors, or electrocautery needs to be re-evaluated in the wake of newer modalities, such as electrothermal bipolar vessel sealing (EBVS) devices, which may theoretically reduce the postoperative complications and morbidity in these patients. Aim and objective The objective of this study is to compare an EBVS device to electrocautery (diathermy) in modified radical mastectomy (MRM), based on selected intraoperative and postoperative outcomes. Study procedure This was a comparative cross-sectional section study that included 60 patients with operable breast cancer (stages I and II, TNM classification, and post-neoadjuvant stage III disease). Patients were divided into two groups for surgery: one group underwent an MRM using the EBVS device (Group A), while the other group had the procedure performed using conventional electrocautery (Group B), as per the surgeon's choice depending on theatre slot and equipment availability. Intraoperatively, the total operative time, time for raising the flaps, time taken for breast tissue dissection, time for axillary dissection, and blood loss were recorded. Postoperative parameters included total drainage volume, number of days of drainage, seroma formation, and other complications. Patients were followed up for one month after surgery, with early postoperative complications such as wound infection, upper limb lymphedema, seroma, flap necrosis, and nerve injuries being documented. Results The groups were found to be comparable in terms of the age distribution, TNM staging, stage grouping, and nodal status of the patients. The EBVS device group demonstrated statistically significant advantages in total operative time, axillary dissection time, flap raising time, breast tissue dissection time, intraoperative blood loss, total drainage volume, and days of drainage. However, no statistically significant difference was found between the two devices in terms of seroma formation, early postoperative complications, and duration of postoperative stay at the hospital. Conclusion While the use of EBVS in MRM provides a considerable decrement in the total operative duration, duration of the various steps of surgery, intraoperative blood loss, and postoperative volume and duration of drainage, these devices do not offer an evident advantage in terms of the postoperative complications or morbidity.

6.
AME Case Rep ; 8: 43, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711888

RESUMO

Background: Autosomal dominant hyper-IgE syndrome (AD-HIES) is a rare genetic syndrome that alters typical post-operative wound healing. AD-HIES patients are prone to develop persistent air leaks (PALs) due to bronchopleural fistulas. This report is unique in that it describes a novel approach to managing PALs in this complex population. Case Description: Two patients with AD-HIES were identified in the setting of a PAL. The first patient was a 31-year-old male with recurrent pneumonia, who developed a large hydropneumothorax following re-presentation with fever and cough. A chest tube was inserted, which required continuous suction in the setting of what developed into a PAL. Subsequently, an endobronchial valve (EBV) was deployed to successfully manage the PAL. The second patient was a 25-year-old male, who developed a post-operative large volume air leak following a complicated surgical resection of a giant pneumatocele. Several attempts of placing multiple EBVs were required to finally address the PAL. In both cases, EBVs were successfully employed to manage and eventually resolve symptoms caused by PAL. Conclusions: Our experience suggests that EBVs are successful in treating PAL in the setting of AD-HIES, which often manifests as highly complex scenarios. Hence, EBVs represent a valuable addition to the therapeutic armamentarium against recalcitrant PAL. EBVs were well-tolerated in patients afflicted by AD-HIES, with no progressive infections noted. Both patients ultimately were able to resolve their PAL following placement of the EBV.

7.
Pathogens ; 11(8)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36015021

RESUMO

Background: Multidrug-resistant pulmonary tuberculosis (MDR-PTB) has become a major cause of high morbidity and mortality related to TB. Conventional drug regimens are ineffective for the treatment of MDR-PTB patients with cavities. This study aimed to evaluate the clinical efficacy and safety of one-way endobronchial valves (EBVs) for the treatment of cavities in MDR-PTB patients. Methods: MDR-PTB patients with positive sputum cultures, sputum smears, and cavities were treated with EBVs in the drainage bronchus of the pulmonary cavity between November 2013 and March 2018. The participants comprised those who had failed previous anti-tuberculosis therapy, as determined by drug susceptibility testing. Results: Thirty-five MDR-PTB patients were included, three of whom were lost during follow-up. The size of the lung cavity was reduced in all of the patients after EBV implantation, including the three lost to follow-up. In the remaining 32 patients, the sputum culture conversion (SCC) rate reached 100%, and the cavity closure rate was 68.8%. There were no significant differences in the cavity closure rate between patients aged ≤40 and >40 years, between the upper and lower lobes, or between the use and non-use of linezolid groups (p > 0.05). Interestingly, the cavity closure rate was higher in women than in men (p = 0.005). Moreover, the cavity closure rate correlated with the time to SCC (correlation coefficient, 0.8933; p < 0.0001). There were no severe adverse events in the patients treated with EBV implantation. Conclusion: EBV installation is effective and safe for the treatment of cavities in MDR-PTB patients. The efficacy of EBV treatment may not be affected by age, disease course, or the location of the lung lobe in the cavity.

8.
Front Immunol ; 12: 640918, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33833760

RESUMO

Epstein Barr virus (EBV) is one of the most successful pathogens in humans with more than 95% of the human adult population persistently infected. EBV infects only humans and threatens these with its potent growth transforming ability that readily allows for immortalization of human B cells in culture. Accordingly, it is also found in around 1-2% of human tumors, primarily lymphomas and epithelial cell carcinomas. Fortunately, however, our immune system has learned to control this most transforming human tumor virus in most EBV carriers, and it requires modification of EBV associated lymphomagenesis and its immune control by either co-infections, such as malaria, Kaposi sarcoma associated herpesvirus (KSHV) and human immunodeficiency virus (HIV), or genetic predispositions for EBV positive tumors to emerge. Some of these can be modelled in humanized mice that, therefore, provide a valuable platform to test curative immunotherapies and prophylactic vaccines against these EBV associated pathologies.


Assuntos
Transformação Celular Viral/imunologia , Coinfecção , Infecções por Vírus Epstein-Barr/imunologia , Linfoma/virologia , Animais , Carcinogênese/imunologia , Transformação Celular Viral/genética , Coinfecção/genética , Coinfecção/imunologia , Coinfecção/virologia , Modelos Animais de Doenças , Herpesvirus Humano 4 , Humanos , Linfoma/genética , Linfoma/imunologia , Camundongos , Vírus Oncogênicos/genética , Vírus Oncogênicos/imunologia
9.
Trends Ecol Evol ; 35(8): 656-667, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32423635

RESUMO

3D-imaging technologies provide measurements of terrestrial and aquatic ecosystems' structure, key for biodiversity studies. However, the practical use of these observations globally faces practical challenges. First, available 3D data are geographically biased, with significant gaps in the tropics. Second, no data source provides, by itself, global coverage at a suitable temporal recurrence. Thus, global monitoring initiatives, such as assessment of essential biodiversity variables (EBVs), will necessarily have to involve the combination of disparate data sets. We propose a standardized framework of ecosystem morphological traits - height, cover, and structural complexity - that could enable monitoring of globally consistent EBVs at regional scales, by flexibly integrating different information sources - satellites, aircrafts, drones, or ground data - allowing global biodiversity targets relating to ecosystem structure to be monitored and regularly reported.


Assuntos
Biodiversidade , Ecossistema , Imageamento Tridimensional , Fenótipo
10.
Int J Parasitol ; 49(12): 901-910, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31585121

RESUMO

Global livestock production is facing serious new challenges, including climate-driven changes in parasite epidemiology, and anthelmintic resistance, driving a need for non-chemotherapeutic methods of parasite control. Selecting for genetic resistance to gastrointestinal nematode infection could reduce reliance on chemical intervention and mitigate increases in parasite challenge due to climate change. Ewes of the composite Exlana breed with a range of estimated breeding values (EBVs) based on nematode faecal egg counts (FECs) were monitored during the peri-parturient period on two farms in southwestern England. Ewes with low EBVs ("resistant") had lower FECs during the peri-parturient period than those with high EBVs ("susceptible"): the mean FEC was reduced by 23% and 34% on Farms 1 and 2, respectively, while the peak FEC was reduced by 30% and 37%, respectively. Neither EBV nor FEC were correlated with key performance indicators (estimated milk yield, measured indirectly using 8 week lamb weight, and ewe weight loss during lactation). Simulations predict that the reduced FECs of resistant ewes would result in a comparable reduction in infection pressure (arising from eggs shed by ewes) for their lambs. Furthermore, although the reduced FECs observed were modest, simulations predicted that selecting for nematode resistance in ewes could largely offset predicted future climate-driven increases in pasture infectivity arising from eggs contributed by these ewes. Selective breeding of the maternal line for nematode resistance therefore has potential epidemiological benefits by reducing pasture infectivity early in the grazing season and alleviating the need for anthelmintic treatment of ewes during the peri-parturient period, thus reducing selection pressure for anthelmintic resistance. These benefits are magnified under predicted future climate change. The maternal line warrants more attention in selective breeding programmes for nematode resistance.


Assuntos
Resistência à Doença , Fezes/parasitologia , Enteropatias Parasitárias/veterinária , Nematoides/crescimento & desenvolvimento , Infecções por Nematoides/veterinária , Doenças dos Ovinos/parasitologia , Ovinos/parasitologia , Animais , Mudança Climática , Inglaterra , Helmintíase/imunologia , Helmintíase/parasitologia , Enteropatias Parasitárias/imunologia , Enteropatias Parasitárias/parasitologia , Nematoides/imunologia , Infecções por Nematoides/imunologia , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas , Seleção Artificial , Doenças dos Ovinos/imunologia
11.
PeerJ ; 7: e7005, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308994

RESUMO

Monitoring of species and populations is essential for biodiversity observation and reporting at local, national and global scales, but can be an exceedingly difficult task for many, if not most, species. We tested the viability of using Google Earth™ imagery to manually map and monitor all individuals of the critically endangered Clanwilliam cedar, Widdringtonia wallichii Endl. ex Carrière, across its global native distribution; the remote and rugged Cederberg mountains. Comparison with sampling from field surveys reveals this to be a highly efficient and effective method for mapping healthy adult tree localities, but it fails to detect small or unhealthy individuals with green canopies <4 m2, or discern the number of individuals in clumps. This approach is clearly viable as a monitoring tool for this species and, with the rapid progress being made in machine learning approaches and satellite technology, will only become easier and more feasible for a greater number of species in the near future. Sadly, our field surveys revealed that the number of trees that have recently died (dead leaves still present) outnumbered live trees by a ratio of 2:1.

12.
Breast Dis ; 35(1): 5-11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25159187

RESUMO

BACKGROUND: Various methods are currently used during axillary lymphadenectomy. Our systematic review aims to investigate the potential benefits of bipolar vessel sealing systems (EBVS) over conventional suture ligation during the axillary dissection of breast cancer patients. METHODS: We searched Medline (1966-2014), Scopus (2004-2014), Popline (1973-2014) Cochrane CENTRAL (1999-2014) and ClinicalTrials.gov (2000-2014) together with reference lists from included studies Statistical meta-analysis was performed using the RevMan 5.1 software. RESULTS: Four studies were finally included, involving 352 patients. Usage of EBVS significantly increased the number of retrieved axillary lymph nodes (MD 1.67 nodes, 95% CI 0.21, 3.13). Intraoperative times were not affected by these new technique, when compared to traditional suture ligation (MD -10.82 minutes, 95% CI -23.27, 2.70). Neither the volume of postoperative axillary drainage (MD -38.47 ml, 95% CI -110.26, 32.59) nor the duration of drainage (MD -0.49 days, 95% CI -1.23, 0.25) were significantly affected by EBVS application. We observed, however, that bipolar systems may be associated with an increased risk of postoperative seroma formation (OR 2.04, 95% CI 1.13, 3.70). CONCLUSION: Electrosurgical bipolar vessel sealing systems seem to increase the accuracy of axillary dissection and are equally safe compared to conventional suture ligation regarding intraoperative and postoperative blood loss. They are associated, however, with and increased incidence of seroma formation. Further randomized trials are needed in the field in order to obtain firm conclusions.


Assuntos
Neoplasias da Mama/cirurgia , Eletrocirurgia/métodos , Hemostasia Cirúrgica/métodos , Excisão de Linfonodo/métodos , Axila/cirurgia , Feminino , Humanos , Linfonodos/irrigação sanguínea , Metástase Linfática , Mastectomia/métodos
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